Luminaire for emitting directional and non-directional light

ABSTRACT

Disclosed is an LED luminaire, comprising a housing positionable at a building structure location. The housing has at least one light output boundary and configured to direct light therein toward the light output boundary. A light guide configured to be located at the light output boundary to receive light operationally contained within the housing, so as to emit non-directional light at the light output boundary. At least one first LED light engine is located within the housing, the at least one first LED light engine including at least one first LED light source to emit directional light at the light output boundary.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation-in-Part of copending U.S. patentapplication Ser. No. 15/466,697, filed Mar. 22, 2017, which is aContinuation-in-Part of U.S. patent application Ser. No. 14/936,371,filed Nov. 9, 2015 (Now U.S. Pat. No. 10,180,521), which claims priorityto U.S. Provisional Application No. 62/077,039, filed Nov. 7, 2014. Thisapplication is also a Continuation-in-Part of copending InternationalPCT application No. PCT/US2015/059770, filed Nov. 9, 2015. Thedisclosures set forth in the referenced applications are incorporatedherein by reference in their entireties.

FIELD OF DISCLOSURE

This disclosure relates generally to the field of illumination productsincluding luminaires, and, more particularly, to a luminaire foremitting directional and non-directional light.

BACKGROUND

Many illumination applications (e.g., luminaires) require control of thelight attributes (e.g., direction or intensity) for both functional andaesthetic purposes. For example, in a workroom, high-intensity light maybe directed toward one or more specific work areas, while the room isilluminated diffusely. Likewise, in a conference room, light maydirected toward the table area, while diffuse, ambient light illuminatesthe rest of the room.

Beyond the need to provide both directional and ambient/diffuse light,Applicants recognize the need to provide ambient light along withdirectional light to reduce glare. Specifically, a luminaire havinghigh-intensity light can cause glare, owing to the stark contrastbetween the luminaire's high intensity light-emitting surface and thesurface surrounding it. Applicants also recognize that glare from highintensity light can be diminished by surrounding the high-intensitylight-emitting surface with diffuse light, thereby reducing theaforementioned contrast.

Traditional approaches for providing both directional and diffuse lightgenerally involve independently illuminating the directional and diffuselight-emitting surfaces. Often this is embodied in two or more differentluminaires. This necessarily requires discrete lighting sources anddriving circuitry, thus adding complexity and cost to the lightingsystem. Other applications involve halogen lamps, which may beconfigured to emit diffuse light backward for aesthetic purposes.However, halogen lamps tend to be inefficient (e.g., about 10-20lumens/W or about 5% of theoretical light-generation efficiency), and,thus are not cost effective to operate.

Therefore, Applicants have identified a need for a luminaire thatprovides both directional and diffuse light in a single luminaire usingefficient LED light sources, but avoids the complexity and cost ofconventional lighting systems. The present invention fulfills this need,among others.

SUMMARY

The following presents a simplified summary of the invention in order toprovide a basic understanding of some aspects of the invention. Thissummary is not an extensive overview of the invention. It is notintended to identify key/critical elements of the invention or todelineate the scope of the invention. Its sole purpose is to presentsome concepts of the invention in a simplified form as a prelude to themore detailed description that is presented later.

Applicants recognize that by optically coupling a directionallight-emitting element with a nondirectional light-emitting surface in a:luminaire, both directional and non-directional light can be can beemitted using the same light source(s). Such a configuration has anumber of advantages. For example, such a luminaire configuration issimple, efficient, and cost effective because the same light source(s)can be used to emit both directional and non-directional light.Additionally, because the different light-emitting surfaces/elements areoptically coupled, the contrast between them is reduced, therebyreducing glare, and generally adding to the esthetics of the luminaire'sillumination. Such a configuration also facilitates the use of othertechnologies for controlling, for example, the direction and color ofthe emitted light. Other features and advantages of the luminaire systemof the present invention will he apparent to those of skill in the artin light of this disclosure.

Accordingly, one aspect of the present invention is a luminaire havingoptically coupled directional and non-directional light-emittingsurfaces. For example, in one embodiment, the luminaire comprises: (a)at least one LED light source for emitting light rays; (b) at least onedirectional light-emitting element optically coupled to the at least oneLED light source to receive at least a portion of the light rays andbeing configured to emit directional light from the luminaire; (c) atleast one waveguide optically coupled to the at least one LED lightsource to receive at least a portion of the light rays; and (d) at leastone non-directional light-emitting element optically coupled to the atleast one waveguide and being configured to emit non-directional light.

In another embodiment, the luminaire comprises: (a) at least onedirectional light-emitting element configured to emit directional lightfrom the luminaire; (b) at least one non-directional light-emittingelement configured to emit non-directional light from the luminaire, theat least one non-directional light-emitting element being opticallycoupled to the at least one directional light-emitting element; and (c)at least one LED light source for emitting light and being opticallycoupled to at least one of the at least one directional light-emittingelement or the at least one non-directional light-emitting element. Inone embodiment, the at least one non-directional light-emitting elementcomprises at least one waveguide.

In another aspect, there is provided an LED luminaire, comprising aluminaire housing defining a light output region. A light guide isconfigured to be located at the light output region. The light guidedefines at least one directional light source location thereon. At leastone LED light engine is located within the luminaire housing andcomprises at least one first LED light source, and a shroud having ashroud periphery, and configured to operatively position the first LEDlight source therein and inwardly spaced from the shroud periphery. Theshroud periphery is positionable adjacent the light guide at thedirectional light source location, to deliver directional light via thedirect light source location to a target location, in a target regionbeyond the luminaire. The light guide is configured to optically couplewith a light source from within the housing to define a non-directionallight output to deliver non-directional light toward the target region.

In another aspect, there is provided an LED luminaire comprising ahousing positionable at a building structure location and having atleast one light output boundary and configured to reflect light thereintoward the light output boundary. A light guide is configured to belocated at the light output boundary to receive light operationallycontained within the housing, so as to emit non-directional light at thelight output boundary. At least one first LED light engine locatedwithin the luminaire housing, the at least one first LED light engineincluding at least one first LED light source to emit directional lightat the light output region.

In another aspect, there is provided a luminaire providing a lightoutput boundary. The luminaire comprises:

-   -   (a) an LED engine adjacent the light output boundary; and,    -   (b) a wave guide facing at least in part the LED engine and        adjacent the light output boundary for receiving a portion of        the output from the LED engine. The wave guide has a removed        portion. The removed portion permits the transmission of        directional light from the LED engine. The wave guide provides        non-directional light from the received portion of output.

BRIEF DESCRIPTION OF DRAWINGS

The drawings, described below, are for illustration purposes only. Thedrawings are not intended to limit the scope of the present disclosure.

FIGS. 1A-1C show embodiments of a light-emitting diode (LED) luminaireof the present invention.

FIGS. 2A-2C depict various embodiments of the luminaire of the presentinvention in which the non-directional light-emitting element isdisposed on an edge of the luminaire to diffuse light along theperimeter of the luminaire.

FIGS. 3A through 3D show different directional light-emitting elementand non-directional light-emitting element embodiments of the luminairedisclosed generally in FIG. 1A.

FIGS. 4A-4B show an alternative embodiment in which the luminairecomprises a waveguide that extends from different sides of thedirectional light-emitting element.

FIG. 5 shows an alternative embodiment of the luminaire of the presentinvention.

FIGS. 6A-6P show various renderings of different embodiments of theluminaire of the present invention to illustrate the directional lightand the non-directional light.

FIGS. 7A-7B show one embodiment of a directional light-emitting elementof the present nvention.

FIGS. 8 to 10A show embodimentsof LED luminaires of the presentinvention.

DETAILED DESCRIPTION

Referring to FIGS. 1A to 1C show embodiments of a luminaire providingboth indirect and direct light sources, where such light sources arederived from a common plane and/or common light source. Indirect lightmay be generally diffuse and thus the light source may usually be asurface on a partially reflective surface or a surface otherwiseconfigured to scatter light incident thereon. Interior surfaces of alight fixture housing may be sources of indirect light as can luminaireoptics, including lenses and light guides. Thus, a direct light maytypically be non-diffuse and may originate directly from a light sourceor be reflected by a surface, or shaped by an optic, which does notscatter the light.

Referring to FIG. 1A, one embodiment of a light-emitting diode (LED)luminaire 100 of the present invention is shown. The luminaire 100comprises (a) at least one LED light source 101 for emitting light rays101 a; (b) at least one directional (direct) light-emitting element 102optically coupled to the at least one LED light source 101 to receive atleast a portion of the light rays 101 a and to emit directional light102 a from the luminaire; (c) at least one waveguide 103 opticallycoupled to the at least one LED light source 101 to receive at least aportion of the light rays 101 a; and (d) at least one non-directional(indirect) light-emitting element 104 optically coupled to the at leastone waveguide 103 and configured to emit non-directional light 104 a.These elements and selected embodiments are described in greater detailbelow.

As used herein, and as understood in the art, directional light raysrefers to light emission patterns having a distribution of intensitywhich is substantially concentrated in an angular range significantlysmaller than 2 pi steradians (for emission in a half-space) or 4 pisteradians (for emission in a full space). For instance, well knownexamples of directional light include distributions characterized by abeam angle at half-maximum, where the beam angle is no more than 40°. Inone embodiment, the beam angle is no more than 30°, and, in a moreparticular embodiment, no more than 10°. A variety of beam profiles meetthis definition including flat-top beams, Gaussian beams and others.

As used herein, non-directional light rays refers to diffuse light,which is well known to those of skill in the art. There are differentways of describing non-directional light. For example, to the extentnon-directional light has a measurable beam angle at half-maximum, thebeam angle is greater than 40°. However, not all light can becharacterized by beams. Alternatively, non-directional light can beconsidered to have a near Lambertian distribution. Likewise, somenon-directional light will have a near isotropic distribution.

The LED light source functions to emit light rays. Such LED lightsources are well known to one skilled in the art. The LED light sourcesmay be configured to emit any kind of light. For example, in oneembodiment, the emitted light from the LED light is white, while inanother embodiment, the light is violet. An LED light source may containa single LED or multiple LEDs. In such an embodiment, the LED lightsources may be configured to emit different light. For example, one LEDmay be a white emitting LED (violet-based and blue-based) and another isa direct violet LED, In some embodiments, the spacing and configurationof the multiple LEDs is configured to obtain a uniform distribution oflight (including intensity, color, color-over-angle, etc. In sonic casesthe materials used for the optics and waveguide are substantiallytransparent to violet light e.g., for instance, the absorptioncoefficient at 400 nm could be 1 cm-1, 0.1 cm-1, 0.01 cm-1, 0.001 cm-1etc. Still other embodiments will be known or obvious to one of skill inthe art in light of this disclosure.

Likewise, a luminaire may have just one LED light source or multiple LEDlight sources. LED light sources may be arranged in array and include,for example, a linear array of LED light sources or an XY matrix of LEDlight sources. For example, referring to FIG. 4A, a luminaire 400 isshown having a single LED source 401, while in FIG. 4B, a luminaire 400′is shown having an array of three LED light sources 401′. Suitable LEDlight sources are commercially available from a number of sources,including, for example, Soraa Inc. (Freemon Calif.).

The directional light-emitting element functions to receive light fromthe LED light source and emit it from the luminaire as directionallight. In one embodiment, the directional light-emitting element isdefined in a discrete directional light-emitting element, such as, forexample, a discrete molded component defining multiplereflective/refractive surfaces—e.g., it may be the output facet of adirectional optical lens such as a reflective lens, a prismatic lens, atotal internal reflection (TIR) lens, or it may be the output facet of areflective reflector optic such as a CPC. and still other embodimentswill be known or obvious to one of skill in the art in light of thisdisclosure. Alternatively, the directional light-emitting element may beintegrally packaged with the LED light source, or it may be integralwith the waveguide, and comprise, for example, surface optics (e.g.,prisms and micro-lenses) defined on the surface of the waveguide totransmit the light out of the waveguide as directional light. Stillother embodiments will be known or obvious to one of skill in the art inlight of this disclosure.

The optics for emitting directional light from the LED light source arewell known. For example, referring to FIG. 7A, a directionallight-emitting element is shown. As shown in FIG. 7A, cross section 700comprises a single point light source engine 701, which includes ahigh-intensity light source 770, a lens body 720, and a glare blocker730. Single point light source engine 701 can have many advantages whenused in multidirectional luminaires with single point source lightengines, such advantages including, in part, small overall size, thinprofile, smooth single-shadow light, tighter or more focused light beams(e.g., 70 degrees), uniform full spectrum color, and the like. In someembodiments, light source 770 can be an LED package subassembly ormodule, comprising a plurality of LEDs coupled to a voltage source(e.g., 720 volts AC) through LED driver circuitry. Further, lens body720 can be monolithic and fabricated via a molding and/or etchingprocess from transparent material (e.g., Makrolon® LED2245Polycarbonate). Also, glare blocker 730 can include a magnet 732 and anopaque plastic cap 733, or can comprise other materials andcombinations.

In some embodiments, lens body 720 further comprises a reflectivesurface 722, a forward-facing lens surface 723, and a light receivingregion 724. Light receiving region 724 can also include a recessed peak725. In some embodiments, recessed peak 725 enables the ratio of height742 to width 743 of lens body 720 to be smaller than would otherwise bepossible. For example, in various embodiments, the height 742 to width743 ratio can be within a range of about 1:5 to about 1:7 (e.g., about 9mm:50 mm). Recessed peak 725 further supports a minimum thickness 744 oflens body 720 between light receiving region 724 and lens surface 723 tomaintain overall strength and integrity of single point light sourceengine 701. In other embodiments, more than one instance of recessedpeak 725 can be used within light receiving region 724. Further, aminimum distance 745 can be maintained between the lens material atrecessed peak 725 and light source 770. In some cases, minimum distance745 is such that light source 770 is outside of light receiving region724 as shown in cross section 700. Additionally, in some embodiments,lens body 720 has a sloped surface 726 above glare blocker 730. Thecentral conical-shaped depression of sloped surface 726 helps divertlight directed toward glare blocker 730 back toward the reflectivesurface 722.

FIG. 7B shows a cross sectional view showing ray paths in a thin profiledirectional light-emitting element that utilizes a double bounce. Shownis an exemplary Ray 779 of the ray bundle from a source, which can be anextended source, that is TIRed at the front flat surface between raysegments 779 ₁ and 779 ₂, then reflected between ray segments 779 ₂ and779 ₃ from the back side mirror, and finally exits the front flatsurface collimated with other rays in the ray bundle. In particular,FIG. 7B comprises single point light source engine 701 shown in crosssection 700 of FIG. 7A. Diagram 700′ further shows light source 770providing a high intensity light into light receiving region 724 asrepresented by a first light ray 771. In various embodiments, the indexof refraction mismatch, the angle of incidence, and other attributes atthe interface between light receiving region 724 and lens body 720, willcause first light ray 771 to bend as it enters lens body 720 asrepresented by a second light ray 772. Similarly, in variousembodiments, the index of refraction mismatch, the angle of incidence,and other attributes at sloped surface 726 will cause second light ray772 to be redirected toward reflective surface 722 as represented by athird light ray 773. Further, in various embodiments, reflective surface722 changes the direction of third light ray 773 to generally bedirected toward forward-facing lens surface 723 as represented by afourth light ray 774. The substantial redirection (e.g., reflection) ofthird light ray 773 to form the fourth light ray 774 can beaccomplished, in part, by a reflective coating on the outside of lensbody 720 at rearward-facing reflective surface. Subsequently, in variousembodiments, the index of refraction mismatch, the angle of incidence,and other attributes at forward-facing lens surface 723 will cause thefourth light ray 774 to be emitted from single point light source engine701 as represented by a fifth light ray 775. Finally, reflective surface722 can be designed (e.g., with gratings) such that a portion of thelight represented by second light ray 772 will be emitted through therear of lens body 720 of single point light source engine 701, asrepresented by a sixth light ray 776. The folded light path depicted bylight rays 771-775 in diagram 700′ enables a tighter collimation oflight than is normally available from legacy light engines of equivalentdepth. In addition to this advantage, the prism optics of single pointlight source engine 701 can have many other advantages when used inmultidirectional luminaires with single point source light engines, suchadvantages including, in part, focused light beam definition, preciselight beam adjustment, efficient light control with a single point lightsource, and the like.

The direction, angles, and other attributes of the light depicted bylight rays 771-776 can be controlled by various techniques andapproaches. For example, the shape or angle of each surface or interfaceupon which light is incident will directly affect the refraction (e.g.,bend) of the light. This control mechanism is implemented, in part, bythe molding or etching process during manufacturing of lens body 720 andrelated components. Further, the choice of materials used inconstructionof single point light source engine 701 will impact therelative indexes of refraction and thus the refraction angles at eachindex transition plane. Other techniques, such as prism optics, can bedeployed to control light direction. For example, reflective surface 722can comprise a plurality of prismatic structures (e.g., triangular,sawtooth, etc.) etched into the material. In some embodiments, theprismatic structures can begin in the inner region of lens body 720 nearlight source 770 and extend toward the outer perimeter of lens body 720along the contour of reflective surface 722. In other embodiments, theprismatic structures can follow other paths along the contour ofreflective surface 722, such as spiral patterns, concentric patterns,scalloped patterns, and the like. The pitch between prisms, the internalangle of the prisms, the peak to trough depth of the prisms, and otherattributes of the prism can further be adjusted to control the overalllight direction and output of each light engine design. In addition,some embodiments can include texturing and/or coating treatments ofvarious surfaces to control light attributes. For example, addingtexture to the sidewall of the prismatic structures on a surface (e.g.,reflective surface 722) will influence the distribution of lightincident on the textured sidewalls to improve the attributes (e.g.,intensity, color, uniformity, etc.) of the light passing through theprismatic structures. The glare cap and sloped surface 726 furtherprovide light control by not only constraining the intensity of light inthe glare range (e.g., about 30-60 degrees), but also conserving thatlight by redirecting it back toward reflective surface 722 to be blendedwith the emitted light from single point light source engine 701.

Although FIG. 7A shows a relatively large optical element, it should beunderstood that the invention may be practiced with a micro-optic aroundindividual dies (for example having a size of 100 μm or 1 mm). In somecases, the LEDs are very small (e.g., 100 μm, 1 mm). The sized of theprimary optic scales with the LED size. Therefore it is possible to havea primary optic having a small output port (such as 1 mm or less, or afew mm). Accordingly, it is possible to couple this light into a thinwaveguide which may facilitate cost savings and semi-flexible orflexible materials.

Generally, although not necessarily, the directional light-emittingelement will have a planar light-emitting surface for emittingdirectional light. The directional light-emitting surface may beconfigured in different ways. For example, it may be circular as shownin FIG. 3B, a rectilinear as shown in FIG. 3D, or any other shape.

It should be understood that the luminaire may comprise one or moredirectional light-emitting elements. For example, referring to FIG. 6A,a luminaire is shown having a single directional light-emitting element,while FIG. 6F a luminaire is shown having three directionallight-emitting elements.

Additionally, the directional light-emitting elements may be acombination of one or more discrete directional light-emitting elementsand one or more directional light-emitting elements integrated with theLED light source or waveguide.

The optical coupling configuration between the directionallight-emitting element and the LED light source can vary. In oneembodiment, the directional light-emitting element receives lightdirectly from the LED light source. In such an embodiment, thedirectional light-emitting element may be optically-coupled to the LEDlight source in a variety of different ways. For example, in oneembodiment, one directional light-emitting element may be coupled toeach LED light source, as shown, for example, in FIG. 6F. Alternatively,in one embodiment, multiple LED light sources are optically-coupled to asingle directional light-emitting element as shown, for example in FIG.4B. In that embodiment, just one directional light-emitting element iscoupled to the array of three LED light sources. In yet anotherembodiment, there may be multiple light-emitting directionallight-emitting elements optically-coupled to a single light source (see,e.g., FIG. 5). Still other embodiments would be obvious to those ofskill in the art in light of this disclosure.

Rather than the directional light-emitting element being opticallycoupled directly with the LED light source, in another embodiment, thedirectional light-emitting element receives light from the LED lightsource through the waveguide. In other words, the directionallight-emitting element is not directly optically coupled with the LEDlight source. In such an embodiment, the directional light-emittingelement may be defined on the waveguide surface. For example, referringto FIG. 5, a luminaire 500 is shown having two waveguides 503 extendingoutwardly from the LED light source 501. On the bottom of eachwaveguide, the directional light-emitting element 502 is defined suchthat the directional light-emitting element emits directional light 502a downward as shown. Alternatively, the directional light-emittingelement may be discrete and optically coupled to the waveguide usingknown optical coupling techniques.

In one embodiment, the luminaire further comprises means of focusing thedirected light from the directional light-emitting element. For example,in one embodiment, the directional light-emitting element can be movedindependently in one or more directions relative to the luminaire, thusallowing the directional light to be targeted on a particular object.Alternatively, rather than physically moving the directionallight-emitting element, lensing can be used to direct the light. Forexample, lenses as disclosed in U.S. application Ser. No. 14/804,060,filed Jul. 20, 2015, hereby incorporated by reference, may be used tofocus the light as shown in FIG. 6N, in which the directional light isfocused on art work, while the non-directional light surrounds thedirectional light-emitting elements, thereby minimizing glare. Stillother embodiments will be known or obvious to one of skill in the art inlight of this disclosure.

In one embodiment, the luminaire further comprises filters or lenses andother color-modifying optical elements to alter the shape orcolor/temperature of the light. Such filters and lenses are disclosed,for example, in U.S. Pat. No. 9,109,760, hereby incorporated byreference.

The waveguide functions to direct the propagation of light from the LEDlight source within certain confines. Such waveguides are well-known andinclude, for example, optically transparent materials, such as glass orplastic having a refraction index significantly different from that ofair such that the interface of the waveguide material and air results ininternal reflection. Alternatively, the waveguide may be hollow and havereflective surfaces to inwardly reflect the light as it propagates downthe waveguide. Still other waveguides suitable for the present inventionwill be obvious to those of skill in the art in light of thisdisclosure.

The waveguide maybe optically-coupled to the LED light source in avariety of different ways as discussed above in connection with thedirectional light-emitting element. For example, in one embodiment, thewaveguide is optically-coupled directly to the LED light source. Forexample, referring to FIG. 5, a luminaire is shown having two waveguidesoptically coupled directly to the LED light source as described above.

Furthermore, like the directional light-emitting element describedabove, the waveguide can be optically-coupled to a single LED lightsource, or multiple waveguides can be coupled to a single light source,or a single waveguide may be optically coupled to multiple LED lightsources. Again, those of skill in the art will understand theseembodiments and others in light of this disclosure.

In another embodiment, the waveguide receives the light rays from thelight source through the directional light-emitting element. Forexample, referring to FIG. 1A, the luminaire 100 is shown having adirectional light-emitting element 102 optically coupled to a waveguide103 on which the non-directional light-emitting element 104 is defined.The directional light-emitting element 102 is coupled to the waveguide103 at its periphery 102B. Light exits the edge 102B of the directionallight-emitting element 102 and enters the waveguide 103. Light enteringthe waveguide 103 from the edge 102B propagates down the light waveguide103 until it reaches a light-emitting surface 104, which emitsnon-directional light 104A. Still other coupling approached will beknown or obvious to one of skill in the art in light of this disclosure.

The waveguide's cross section may vary according to the application. Forexample, it may be flat, curved, wedge-shaped, undulating, etc.Furthermore, the waveguides may be configured in a variety of ways withrespect to the directional light-emitting element. For example, in oneembodiment, the waveguide encircles the directional light-emittingelement as shown in FIG. 6B. Furthermore, referring to FIGS. 6F-6G, aluminaire is shown in which a single waveguide encircles multipledirectional light-emitting elements in an undulating shape and in arectilinear shape, respectively. In another embodiment, discretewaveguides extend in different directions from one or more directionallight-emitting elements as shown in FIG. 5.

The waveguide can be designed with various dimensions (e.g., height,curvature, etc.) and features (e.g., surface structures, translucencygradients, color gradients, etc.) to provide control of the attributes(e.g., direction, intensity, color, etc.) of indirect light.Specifically, in some embodiments, waveguide can have a light transitionarea at which light from single point light source can be transmittedfrom light-emitting into waveguide. More specifically, in someembodiments, at least a portion of light-emitting element can be bondedto the waveguide to eliminate air gaps, decrease surface reflectionsand/or eliminate any lens effect between the light-emitting portions andthe waveguide, thereby reducing light loss and increasing the lightoutput from waveguide. Further, in some embodiments, waveguide caninclude reflective or refractive surfaces (e.g., prismatic structures)for changing the path of a portion of the light from single point lightsource that would not normally enter waveguide at an acceptable angle,allowing light to remain in waveguide for a longer period of time and/orincrease the efficiency of waveguide.

The non-directional light-emitting element functions to receive lightfrom the waveguide and emit non-directional light rays as describedabove. Configurations for the non-directional light-emitting element arewell known in the art. For example, in one embodiment, thenon-directional light-emitting element is integrated with the waveguide.For example, referring to FIG. 1A, a luminaire 100 is shown in which thenon-directional light-emitting element 104 is a portion of the surfaceof the waveguide. In this embodiment, optical element(s) may be disposedon a surface of the waveguide to facilitate the emission of light fromthe waveguide. Such surface structures include, for example, microlenses, prisms, roughening, channels, grooves, and the like. In someembodiments, the waveguide may also include a pattern of lightextracting deformities or disruptions (e.g., prismatic structures) whichprovide a desired light output distribution from waveguide by changingthe angle of refraction of a portion of the light from one or more lightoutput areas of waveguide. For example, non-directional light fromwaveguide can be controlled to emit only in a downward direction, anupward direction, or horizontally from the edge, or any combination ofthese directions.

Alternatively, the non-directional light-emitting element may be adiscrete non-directional light-emitting element optically coupled to thewaveguide. Suitable non-directional light-emitting elements will beobvious to those of skill in the art in light of this disclosure. Forexample, in one embodiment, the non-directional light-emitting elementis an optical element configured to receive light from the waveguide andhaving a surface or volume comprising light scattering features todiffuse light.

In one embodiment, the spectrum emitted from the directionallight-emitting element and the spectrum emitted from the non-directionallight-emitting element are different. For instance, in one embodiment,the correlated color temperature (CCT) of the directional light and thatof the non-directional light are different by using, for example, thetechniques disclosed in U.S. application Ser. No. 14/191,679, filed Feb.27, 2014, herein incorporated by reference. In one particularembodiment, the non-directional light is configured to have a glowingedge, which may, for example, represent the “brand color” of a company.

As mentioned above, the non-directional light-emitting element isconfigured to substantially reduce glare by reducing the contrastbetween the directional light-emitting eleme and the non-directionallight-emitting element. In one embodiment, the non-directionallight-emitting element is configured with a light intensity such that itemits a relative amount of luminous flux at angles 70-90° (from thevertical plane) which is less than 10%, preferably less than 3%, morepreferably less than 1%, and even more preferably less than 0.1% of thetotal luminous flux of the system.

It should be noted that various features described herein may be mixedand matched to provide many permutations of the luminaire of the presentinvention.

Some of the embodiments described above are illustrated in the attachedfigures.

Referring to FIGS. 1A-1C, schematic cross sections showing ray diagramof certain embodiments of the luminaire of the present invention areshown. The luminaire 100 is shown has an LED light source 101. It shouldbe understood that the light 101 shown in this embodiment may be asingle LED light source or it may be a plurality of LED light sources101 arranged in a linear array essentially running perpendicular to thepage. The luminaire 100 also has an essentially flat waveguide. In theparticular embodiment of FIG. 1A, the top and bottom surfaces of thewaveguide are configured to be the non-directional light-emittingelements 104 as described above. Additionally, in this embodiment, thedistal end 103A of the waveguide comprises a diffuse optical element(lens or other element) such that light reaching the distal end 103A ofthe waveguide 103 is diffused. In such an embodiment, the diffuse lensis part of the non-directional light-emitting elements. Alternatively,rather than disposing a diffuse lens at the distal end 103A of thewaveguide, a reflective surface may be used such that the light isreflected back through the waveguide, thereby facilitating its exitthrough the non-directional light-emitting elements 104 on the topand/or bottom surface of the waveguide 103.

Referring to FIG. 1B, another embodiment of the luminaire 100′ is shownwhich is similar to that as described with respect to FIG. 1A, exceptthe distal ends 103a′ of the waveguide 103′ are tapered, thereby causingthe light to exit the non-directional light-emitting element 104′through the bottom as shown. Specifically, light entering the waveguide103′ from the edge 102B′ of the directional light-emitting elementpropagates down the waveguide 103′ towards the distal end 103A′ of thewaveguide. As the light propagates, the waveguide becomes thinner,effectively squeezing non-directional light 104 a′ out through thenon-directional light-emitting element 104′ defined on the bottom of thewaveguide as shown.

Referring to FIG. IC, yet another embodiment luminaire 100″ is shown.This embodiment is similar to that of FIG. IA except that the waveguides103″ are angled inward, thereby focusing the directional light. Withrespect to the waveguide 103″ it should be understood that, as shown inthis cross section, the waveguide 103″ may comprise two (2) discretewaveguides that are elongated running essentially perpendicular to thepage, or, alternatively, it may comprise a single waveguide thatencircles the directional light-emitting element 102″ optically coupledto the LED light source 101″ as discussed for example in FIG. 3B-C.

FIGS. 2A-2C depict various embodiments of the luminaire of the presentinvention in which the non-directional light-emitting element isdisposed on edge of the luminaire to diffuse light along the perimeterof the luminaire. The embodiment of FIG. 2A has the directionallight-emitting element 202 is defined on the bottom of the luminairesuch that light from light source 201 is emitted as directional light202A downward, while light propagating down along the waveguide 203 isemitted as non-directional light 204A along the edge or perimeter of theluminaire from the non-directional light-emitting element 204.

Referring to FIG. 2B, a second embodiment of the luminaire 200′ isshown. This embodiment is substantially similar to that of FIG. 2A,except the non-directional light-emitting element 204′ at the end of thewaveguide 203′ has one or more facets for the emitting non-directionallight 204A′. In FIG. 2C, another embodiment of the luminaire 200″ isdisclosed, in which the non-directional light-emitting element 204comprises a number of lenses, such as ellipsoid lenses, which serve toemit non-directional light 204A in a decorative pattern.

FIGS. 3A through 3D show different directional light-emitting elementand non-directional light-emitting element embodiments of the luminairedisclosed generally in FIG. 1A. Like luminaire 100, luminaire 300comprises a light source 301, a reflective housing 305, a directionallight-emitting element 302 to receive the light rays from the lightsource 301 and to admit directional light 302 a. Additionally, thedirectional light-emitting element 302 is optically-coupled to thewaveguide 303 such that light rays from the light source 301 areoptically-coupled into the waveguide 303 and then are emitted by thenon-directional light-emitting element 304 as non-directional light 304a. As mentioned above with respect to FIG. 2A, there are differentembodiments of the waveguide 303. For example, referring to FIG. 3B, asquare waveguide 303′ surrounds or encircles a circular directionallight-emitting element 302′. In the embodiment of FIG. 3C, a circularwaveguide 303″ encircles a circular directional light-emitting element302″.

In the embodiment of FIG. 3D, an elliptical waveguide 303′ encircles asquare directional light-emitting element 302′. Still other embodimentswill be known to those skilled in the art in light of this disclosure.

Referring to FIG. 4A, an alternative embodiment is disclosed in whichthe luminaire 400 comprises a waveguide 403 that extends from differentsides of the directional light-emitting element 402. The directionallight-emitting element 402 emits directional light downward, toilluminate, for example, a table top. In such an embodiment, thenon-directional light-emitting element 404 may be, for example, on theunderside of the waveguide 403 to reduce glare. Alternatively, or inaddition to, the non-directional light-emitting element 404 may bedefined on the top of the waveguide 403 to provide ambient light. Thewaveguide portion 403 can be designed with various dimensions (e.g.,height, curvature, etc.) and features (e.g., surface structures,translucency gradients, color gradients, etc.) to provide control of theattributes (e.g., direction, intensity, color, etc.) of indirect light.It should be also understood that the waveguide; 403 may comprise twodiscrete waveguides that extend on either side of the directionallight-emitting element 402 and perpendicular to the page. In anotherembodiment, it may comprise a single waveguide that extends around thedirectional light-emitting element 402.

As shown in FIG. 4B, the luminaire 400′ may have waveguides that areasymmetrical about the LED light source 401′. In this embodiment, thereis an array of three (3) LED light sources 401′. Here, the waveguidethat extends on either side of the LED light sources 401′ is a singlewaveguide. Again, still other embodiments will be known of skill in theart in light of this disclosure.

Referring to FIG, 5, an alternative embodiment of the luminaire 500 isshown. In this embodiment, the light source 501 is directly coupled intothe waveguides 503 which extend downward and outwardly from the lightsource 501. In this embodiment, the directional light-emitting element502 is defined on the underside of the waveguide 503 such that it emitsdirectional light 502 a as shown. The distal end 503 a of the waveguide503 is configured with a light-emitting surface 504 on the upward-facingside such that the non-directional light-emitting element 504 emitsnon-directional light 504 a upward and outward from the luminaire 500 asshown. In this particular embodiment, the waveguides 503 are discreteand are pivotally attached to the light source 501 such that they canmove independently with respect to the light source 501.

Considering FIG. 5 in greater detail, FIG. 5 shows a luminaire 551having a single point light source engine 552, a first waveguide portion554 ₁, a second waveguide portion 554 ₂, a first waveguide pivot 553 ₁,and a second waveguide adjustment pivot 553 ₂. As show in the side view,luminaire 551 emits a substantial amount of available light intensityfrom single point light source engine 552 through waveguide portions 554₁ and 554 ₂ as a first downward light portion 560 ₁ and a seconddownward light portion 560 ₂, respectively. Downward light portions 560₁ and 560 ₂ can serve a functional purpose (e.g., lighting a table top)in some embodiments. Luminaire 501 can also emit a first indirect lightportion 570 ₁ and a second indirect light portion 570 ₂ throughwaveguide portions 554 ₁ and 554 ₂, respectively. Indirect light portion570 ₁ and indirect light portion 570 ₂ can serve a secondary purpose,such as providing ambient light or an aesthetic glow around waveguideportions 554 ₁ and 554 ₂ of luminaire 551. waveguide portions 554 ₁ and554 ₂ can be designed with various features (e.g., surface structures,translucency gradients, color gradients, etc.) and adjusted usingwaveguide pivots 553 ₁ and 553 ₂ to provide control of the attributes(e.g., direction, intensity, color, etc.) of downward light portions 560₁ and 560 ₂ and indirect light portions 570 ₁ and 570 ₂.

Specifically, in some embodiments, waveguide; portions 554 ₁ and 554 ₂can utilize waveguide pivots 553 ₁ and 553 ₂, respectively, to rotateabout an axis normal to the side view and centered at waveguide pivots553 ₁ and 553 ₂, respectively. Such rotation allows direct control ofthe direction of downward light portions 560 ₁ and 560 ₂ and indirectlight portions 570 ₁ and 570 ₂. For example, the table top area coveredby downward light portions 560 ₁ and 560 ₂ can be increased by anoutward rotation of waveguide portions 554 ₁ and 554 ₂, increasing theinner distance between the two waveguide portions. Additionally,waveguide portions 554 ₁ and 554 ₂ can have a light transition area atwhich light from single point light source engine 552 can be transmittedinto both waveguide portions 554 ₁ and 554 ₂. More specifically, in someembodiments, at least a portion of single point light source engine 552can be embedded, potted or bonded to waveguide portions 554 ₁ and 554 ₂to eliminate air gaps, decrease surface reflections and/or eliminate anylens effect between single point light source engine 552 and waveguideportions 554 ₁ and 554 ₂, thereby reducing light loss and increasing thelight output from waveguide portions 554 ₁ and 554 ₂. Further, in someembodiments, waveguide portions 554 ₁ and 554 ₂ can include reflectiveor refractive surfaces (e.g., prismatic structures) for changing thepath of a portion of the light from single point light source engine 552that would not normally enter waveguide portions 554 ₁ and 554 ₂ at anacceptable angle, allowing light to remain in waveguide portions 554 ₁and 554 ₂ for a longer period of time and/or increase the efficiency ofwaveguide portions 554 ₁ and 554 ₂. In some embodiments, waveguideportions 554 ₁ and 554 ₂ can also include a pattern of light extractingdeformities or disruptions (e.g., prismatic structures) which provide adesired light output distribution (e.g., downward light portions 560 ₁and 560 ₂ and indirect light portions 570 ₁ and 570 ₂) from waveguideportions 554 ₁ and 554 ₂ by changing the angle of refraction of aportion of the light from one or more light output areas of waveguideportions 554 ₁ and 554 ₂. For example, indirect light 570 ₁ and 570 ₂from waveguide portions 554 ₁ and 554 ₂, respectively, can be controlledto emit only in an upward direction or horizontally from the edge, orany combination of these directions.

FIGS. 6A-6P show various renderings of different embodiments of theluininaire of the present invention, to illustrate the directional lightand the non-directional light.

FIGS. 6A through 6B depict various embodiments of the luminaire of thepresent invention in which the non-directional light-emitting element isdisposed on edge of the luminaire to diffuse light along the perimeterof the luminaire. In FIG. 6A the luminaire is shown having a directionallight-emitting element 613 emitting directional light 610 downward, anda non-directional light-emitting surface 612 encircling the directionallight-emitting element 613 and emitting non-directional light 611outwardly from the edge of the luminaire. FIG. 6B shows a luminairesimilar to the of FIG. 6A in which the luminaire of 6A is incorporatedinto a larger lamp structure 614 such that the non-directional light 611is incident upon the lamp structure 614 to illuminate it.

FIGS. 6C-6C2 show different embodiments of the luminaire in which thenon-directional light-emitting element encircles the directionallight-emitting element, and emits non-directional light in various waysi.e., downward, outward and/or upward. FIG. 6C is a ray diagram showingthe configuration of the luminaire 300 of FIG. 3A which is shown inperspective view in FIG. 6C1. Specifically, a circular waveguide 615encircles the directional light-emitting element 617, and thenon-directional light-emitting element 618 is the top and bottomsurfaces of the waveguide 616. As shown, this embodiment demonstrateshow the directional light-emitting element 617 emits a directional lightwhile the non-directional light-emitting element 618 emits a diffuselight. The embodiment of FIG. 6C2 is similar to FIG. 6C1, except onlythe bottom of the waveguide 616 is configured as the non-directionallight-emitting element.

FIGS. 6D1-6D2 show embodiments of the luminaire of the present inventionin which the waveguide encircles and directional light-emitting elementand provides a shade for the directional light. Specifically, FIG. 6D1shows an embodiment in which the waveguide 619 encircles the directionallight-emitting element 620 and extends downward in a traditional conicallamp shape to emit diffuse light on the interior of the waveguidestructure 619, thus mimicking a shade. Referring to FIG. 6D2 anotherluminaire is shown similar to that of FIG. 6C, but with the waveguide621. extending down in a rectilinear lamp shade configuration.

FIGS. 6E-6J show embodiment in which a hanging luminaire is comprised ofmultiple directional light-emitting element. In FIG. 6E, an assemblymultiple luminaires such as those disclosed in FIG. 6B is shown.Referring to 6F, another embodiment is shown in which a. commonundulating waveguide 622 envelopes a plurality (3) directionallight-emitting elements 623 to provide diffuse light around each of thedirectional light-emitting elements 623. Referring to 6G, a luminairesimilar to that of FIG. 6F is disclosed in which the waveguide is notundulating but rather recta linear. Referring to FIG. 6H, a luminaire isdisclosed comprising an array of luminaires such as those disclosed inFIG. 3B. Referring to FIG. 61, another luminaire is disclosed in whichthe luminaire comprises a plurality of independently movable waveguides625. A plurality of directionallight-emitting elements 624 are disclosedon each waveguide 625. The waveguides 625 are configurable such thatthey can be moved independently of other waveguides 625 of theluminaire, thereby individually controlling the direction of thedirectional light 624A of each waveguide 625.

Referring to FIG. 6J, another embodiment of luminaires disclosed inwhich a single waveguide or sections of waveguide are combined to form asingle waveguide 626 containing plurality of directional light-emittingelements 627. In this embodiment, as in some of the others, thedirectional light-emitting elements each comprise an LED light source(not shown). It should be understood from FIG. 6J that variousembodiments of this configuration can be used to essentially snakethrough an office providing both high intensity directional light with abackground of diffused light to thereby minimize glare as discussedabove.

FIGS. 6L-6M shows luminaires having multiple directional light-emittingelement configured to be integrated with a typical drop ceiling.Referring to FIG. 6M an embodiment in which the luminaire is configuredhaving the same form factor as a conventional drop-ceiling fluorescentlight. In this embodiment, the waveguide 628 is rectilinear and servesto provide a diffused background for the directional light-emittingelement and thereby eliminate glare.

FIG. 6N shows luminaires that the emitted directional light from thedirectional light-emitting elements is individually controllable so thatthe directed light may be focused on artwork or similar objects alongthe wall or in the room.

FIGS. 60-6P show different embodiments of an overhead luminaire, havinga directional light-emitting element running down the center of theluminaire to emit a thin directional beam 640, and non-directional light641 emitting above and below the waveguides 642 that extends downward oneither side of the directional light-emitting element. The embodiment ofFIG. 6P is similar to that of FIG. 60, except the waveguides extendupwardly.

Referring to FIG. 6K, an embodiment is shown in which a luminaire 660 isconfigured with a wedge-shaped waveguide 661. Different sides/edges ofthe waveguide are configured with various directional light emittingelements 662-664 to focus directed light 662 a, 663 a, and 664 a onvarious objects in the room. Optionally, an edge 665 of the waveguide isconfigured to have a non-directional light-emitting element to emitdiffuse light into the room. Still other embodiments will be known orobvious to one of skill in the art in light of this disclosure.

FIGS. 8 and 9 show, in cross section, another embodiment in the form ofLED luminaire 800, comprising a recessed luminaire housing 802 defininga light output region 804 adjacent one or more ceiling tiles or otherceiling structures shown at 806. Other non-recessed configurations mayalso be deployed, such as with pendant luminaires as shown for instancein one or more of FIGS. 6A to 6F, in which the light output region 804is not adjacent ceiling tiles or other ceiling structures. A light guide808 is configured to be located at, or near, the light output region 804and defines at least one, in this case a plurality of directional lightsource locations 810 thereon, as shown in FIG. 9.

At least one LED light engine is provided at 812 and is located withinthe luminaire housing 802. The LED light engine 812 includes at leastone first LED light source 814. A shroud is provided at 816 which has ashroud periphery 818 and is configured to operatively position the firstLED light source 814 therein and inwardly spaced from the shroudperiphery 818. Thus, in this embodiment, the at least one LED lightengine is, when viewed in FIG. 8, above the upper surface 808 a, so thatthe entire thickness of the light guide 808 is below the at least oneLED light engine.

The shroud periphery 818 is positionable adjacent the light guide 808 atthe directional light source location 810, to deliver the directionallight (as shown by arrows D) via the directional light source location810 (and in this case transversely through the light guide 808) to atarget location (not shown), in a target region beyond the luminaire800.

The light guide 808 is further configured to optically couple with asource of light from within the housing 802 to define a non-directionallight output to deliver non-directional light (as schematically shown byarrows N) in this case toward the target region. In the embodiment ofluminaire 800, the source is the first LED light source.

In an embodiment shown in FIG. 9A, the first LED light source 814 mayalso be configured to deliver non-directional light to the light guide808 to be propagated along the light guide and to emit non-directionallight N therefrom by way of optical characteristics of the light guideas discussed hereinabove for this purpose. In this case, the light guide808 may be configured to receive light from other sources in the housing802 to be emitted as non-directional light N.

In an embodiment shown in FIG. 9B, the first LED light source 814 mayalso be configured to direct light into the housing 802 to be reflectedback to the light guide and emitted therefrom also as non-directionallight N.

Another embodiment is shown, in cross section, in FIG. 10 in the form ofluminaire 830, in which the source is a second LED light source 832, aswill be further discussed hereinbelow.

Referring to FIG. 9, the light guide 808 extends along a path 824. Inthis embodiment, a plurality of LED light engines are provided at 812,each of which is associated with a corresponding directional lightsource target location 810. The directional light source locations maybe arranged in a designated pattern on the light guide 808 to provide adesired optical effect. For instance, the pattern may be in the form ofsingle or multidimensional array, such as in a planar or nonplanarlinear, curved, circular or other configuration, examples of which maybe seen in FIGS. 6A to 6P as well as others.

Referring to FIG. 8, the shroud periphery 818 may be secured to thelight guide 808 adjacent the directional light source location 810, byway of a flange which may be fused by chemical, ultrasonic or otherbonding/welding techniques to a surface region of the light guide 808.The directional light source location 810, in this case, includes apassage 826 through the light guide within (i.e. inside thecircumference of) the shroud periphery 818. In this case, the first LEDlight source and/or the shroud is configured to deliver directionallight transversely through the passage 826.

In the embodiment of FIG. 8, the light guide 808 is configured tooptically couple with the first LED light source 814, via a pathexternal to the shroud 816 but within the luminaire housing 802, such asshown by the plurality of chain-dotted arrows N emanating from the firstLED light source 814 into the luminaire housing 802, reflecting off theinner surfaces thereof and back toward the light guide 808. In thiscase, the shroud 816 may be configured to direct (or redirect) a portionof LED light from the first LED light source into the space of theluminaire housing 802.

In the embodiment of FIG. 10, as mentioned above, the luminaire 830provides a second LED light source 832 located so as not to be withinthe shroud 816 but within the luminaire housing 836, in this casemounted at a designated location in the luminaire housing 836, such asin an upper region thereof to direct light toward the light guide 808for optical coupling therewith to deliver the non-directional light.

Referring to FIG. 10A, the second light source 832 may also providedirectional light D to propagate through the light guide, either as asupplement or an alternative to the directional light D from the firstlight source 814.

The arrows D and N in FIGS. 8 to 10A are schematic only, it beingunderstood that actual ray paths will depend on such things as theoptical geometry and/or characteristics of the light guide 808, thefirst LED light source 814, the second LED light source 832, theinterior surfaces of the luminaire housing 836 and the like.

Thus, luminaires in some embodiments may provide both a directional(direct) point source together with non-directional (indirect) light,thus combining accent or task lighting with general lighting in the sameplane and, in this instance, in the same luminaire. Further, as shown inluminaire 800, some embodiments may derive both indirect and directlight from the same light source. This may permit the colour of theindirect and direct sources to be matched, providing better performanceto previous products, and in some cases at reduced cost.

Some embodiments as shown by luminaires 800 and 812 may provide ahousing positionable at a building structure location, which may be aceiling or a wall and in a designated operable recessed, pendant orexternally positioned relative thereto. The housing may have at leastone light output boundary which is configured to reflect light thereintoward the light output boundary. A light guide may also be providedwhich is configured to be located at the light output boundary toreceive light operationally contained within the housing, so as to emitnon-directional light at the light output boundary. In addition, atleast one first LED light engine may be located within the luminairehousing, wherein the at least one first LED light engine includes atleast one first LED light source to emit directional light at the lightoutput boundary.

In some embodiments, the at least one first LED light engine may includea reflective shroud to emit the directional light toward a directionallight source location on the light guide. In some cases, the shroud maybe in contact with an internally exposed surface of the light guide andthe shroud may be affixed to the internally exposed surface. Thedirectional light source location may include a passage through thelight guide.

In some embodiments, the shroud may be configured to emit or direct aportion of light from the LED light source into the housing to providethe light operationally contained within the housing.

In some embodiments, at least one second LED light source may beprovided in the housing and configured to emit the light operationallycontained within the housing to be emitted from the light guide asnon-directional light and/or configured to emit directional light towardand through the light guide.

Some embodiments may also provide a luminaire providing a light outputboundary, in which the luminaire may comprise an LED engine adjacent thelight output boundary. A wave guide may face, at least in part, the LEDengine and be adjacent the light output boundary for receiving a portionof the output from the LED engine. The wave guide may have a removedportion which permits the transmission of directional light from the LEDengine, and the wave guide may provide non-directional light from thereceived portion of output.

While this description is made with reference to exemplary embodiments,it will be understood by those skilled in the art that various changesmay be made and equivalents may be substituted for elements thereofwithout departing from the scope. In addition, many modifications may bemade to adapt a particular situation or material to the teachings hereofwithout departing from the essential scope. Also, in the drawings andthe description, there have been disclosed exemplary embodiments and,although specific terms may have been employed, they are unlessotherwise stated used in a generic and descriptive sense only and notfor purposes of limitation, the scope of the claims therefore not beingso limited. Moreover, one skilled in the art will appreciate thatcertain steps of the methods discussed herein may be sequenced inalternative order or steps may be combined. Therefore, it is intendedthat the appended claims not be limited to the particular embodimentdisclosed herein.

1. An LED luminaire, comprising: a luminaire defining a light outputregion; a light guide configured to be located at the light outputregion, the light guide defining at least one directional light sourcelocation thereon; at least one LED light located within the luminaire,comprising: at least one first LED light source; and a shroud configuredto operatively position the first LED light source therein and inwardlyspaced from the shroud; the shroud being positionable adjacent the lightguide at the directional light source location, to deliver directionallight via the directional light source location to a target location, ina target region beyond the luminaire; the light guide being configuredto optically couple with the first LED light source in the luminaire todefine a non-directional light output to deliver non-directional light.